just as expected!
love this lens.
i have a 5D mark 1 w/ came with the 24-105L as a kit so im used to the vivid colors of the L lens. been using it for awhile but got tired of shooting indoors! so i bought a 1.8 just to try out, love the result, no stalling , quick focus etc.
since using this for a awile i decided the 50mm is all i need for what i use the camera for so then i sold the 24-105 and the 50 to get this.
im so glad and happier eversince! plus love how it dwarfs the camera, this thing is huge! but i love it!
March 29, 2013

Great Lens
I've been putting off purchasing this lens for a while because of it's back focus (focus shift) problem which occurs only when photographing at extremely close distance using the center focus point of the camera.
However, once I found out that this back focus problem can be overcome by simply using a different focus point, I went for it and bought the lens.
I absolutely love the lens and I'm very happy with my purchase. I simply love the contrast and sharpness this lens produces. And the bokeh is so beautiful.
At 1.2 f/stop, the images are a bit soft because of the extreme width of the aperture, however, the lens gets sharper as you stop down.
I've taken some great image at 1.2 f/stop that look beautiful and sharp, and contrasty.
February 2, 2013

Excellent lens if you know what are you getting
My copy had strong back focus from f1.2 out of box. This shouldn't be the quality of the lens at this price range. I had to micro-adjust to -14 to focus correctly. I tested about two to three feet distance. It seems to me more you stop down, focus moving backwards in a very small increment. I was aware of focus shift issue on this lens before the purchase and found out to be true. It’s there. Now I micro-adjusted focus right on spot at f2.0. So it’s very slightly front focus on f1.2. You start noticing back focus from around f2.8 on until DOF kicks on. To me focus shift won't be too critical in most cases. I’ve read other reviews and I guess some people had the same issue as my copy, which made me feel a little better knowing that I’m not the only one. It is reasonably sharp from f1.2. It’s definitely sharper when stopped down. It sometimes creates color fringe ghosting at f1.2 that makes images look quite soft, but I’ve shot some images that are definitely not soft. At f1.2 DOF is pretty thin, and I've got some hit and miss on focus but that could be camera’s lack of auto focus capability also.
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In real life shooting, this lens produces fantastic images as I expected. Now the focus is adjusted, it’s been such joy playing around with it. Bokeh is very nice and creamy. I love the colors that come out of this lens. Portraits with wide aperture create a certain atmosphere. Built quality is of typical L lenses.
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I have been using EF 50mm f1.8 Mark I. This is also one of my favorite lenses I ever owned. My copy is an old lens from 1987. It’s noisy but very sharp and performs good focus ability. (In fact if you can find a good copy, I highly recommend it.) Comparing these two lenses, there’s no question that f1.2L is superior in every way. But f1.8 Mark I isn’t all bad at all. So the question is f1.2L worth ten times more money? It’s hard to justify if you don’t need wider aperture, better bokeh, USM, or rugged built. But you surely get the satisfaction of owning one.
August 25, 2012

My favorite lens, bar none.
This lens is often maligned as extremely fast glass sometimes is. I feel it absolutely does not deserve this reputation. When used (and possibly configured) properly this lens produces gorgeous results. I never leave this lens behind.
If you're shooting a portrait wide open from 1.5 meters away the depth of field is so shallow that while the subject's eye is in focus the tip of her nose certainly won't be. If the photographer isn't aware of this behavior she probably should stop down and use a flash. That being said, if you do stop down this lens behaves like a high quality slower normal (50mm!) should. It's sharp as heck. I've shot some (unexpected) landscapes and even some action shots with it, despite its heft. AI servo isn't explicitly recommended with this lens, but I've gotten away with it.
Regarding my statement about properly configuring: I found that to achieve optimal results on a full frame body (5d mark II, and now my new mark III) I had to micro-adjust the the body to the lens. This was imperative to achieve sharp shots at f/1.2-f/1.6 or so. Some also say this lens focus-shifts at approximately f/2.0-f/4.0 or so due to it not having a floating rear element. I've not noticed this behavior but this phenomenon may be real for some.
I do feel this lens is a little too spendy, but after experimenting with the 50mm f/1.4 I'm happy I bought the most expensive of the three 50s Canon produces. The build quality of this lens is fantastic, and it's definitely rugged. I've dropped my copy on a hardwood floor at least three times and it's none the worse for wear.
If you like low-light photography and shallow depth of field.. do yourself a favor and get this gem. If you're used to shooting with what used to be called normal focal length (50mm) get this gem! You'll be happy you did.
March 29, 2012